One-piece breech block for automatic firearms with pivoted locking members



June 10, 1952 RT ONE-PIECE BREECH BL. R AUTOMA -C FIREARMS WITH PIVOTEDLO ING MEMB S Filed April 11, 1946 r 4 Sheets-Sheet l 2 59 ll 6 r 3/m/em0r H N/v5 L/PPERT 43 v W A ffornqya H. LIPPERT 2,600.007

o x FOR AUTOMATIC FIREARMS LOCKING MEMBERS June 10, 1952 ONE-PIECEBREECH B WITH PIVO Filed April 11. 1946 4 Sheets-Sheet 2 //2 Van forJune '10, 1952 UPPER-r 2,600,007

ONE-PIECE BREECH BLOCK FOR AUTOMATIC FIREARMS 0 WITH PIVOTED LOCKINGMEMBERS Filed April 11. 1946 v 4 Sheets-Sheet s Fig. 8. I

//7 vemar 2416 I4 I HAN/w; L/PPE'RT 4f fornqys June. 10, 1952 I -r2,600,007

' ONE-PIECE BREECH BLOCK FOR AUTOMATIC FIREARMS WITH PIVOTED LOCKINGMEMBERS 4 Sheets-Sheet 4 Filed April 11, 1946 Fig. I0

Fig. n 33 Avi a/#0, HAN/vs L/PPEET A vfarn gys Patented June 10, 1952ONE-PIECE BREECH BLOCK FOR AUTO- MATIG FIREARMS WITH PIVOTED LOCKINGMEMBERS Hanns Lippert, Zurich, Switzerland, assignor toVerwaltungsgesellschaft der Werkzeugmaschinenfabrik Oerlikon,Zurich-OerIikon, Switzerland, a firm Application April 11, 1946, SerialNo. 661,310

In Switzerland April 21, 1945 3 Claims. 1

Automatic fire arms may be subdivided into two groups according to theirbreach mechanism, viz. those one-piece and those with two-piece breech.Automatic fire arms with one-piece breech involve the necessity of abarrel recoil in order to actuate the breech mechanism, whilst inautomatic fire arms with two-piece breech the control of the breechmechanism is effected by the relative motion of one breech part inrelation to the other.

It is obvious that in the interest of simplicity it would be desirableto use exclusively one-piece breeches. Existing types of fire arms withonepiece breech, however, are of intricate design, in view of the factthat for locking the breech mechanism, in addition to the barrel withthe breech casing rigidly connected with it, and the breech block movinginside it, a casing rigidly fixed in a cradle is required forcontrolling the mechanism for locking the breech block in the breechcasing. For this reason, experience has shown that fire-arms equippedwith one-piece breech involve a substantially more intricate andexpensive design than fire-arms with a two-piece breech. This is,however, the only drawback connected with fire arms equipped withonepiece breech, whilst automatic fire arms with two-piece breechinvolve numerous disadvantages. For instance, fire arms with two-piecebreech must, as a rule, be designed as gas operated guns if it is notconsidered advisable to use for this purpose the barrel recoil, in orderto bring about, by means of a catapult, the rearward motion of the onebreech part carrying out the locking operation.

Practice has further shown that in the course of the locking operationthe rear breech part striking the front breech part is liable torebound. For this reason, the gunners safety can only be assuredprovided ignition takes place within the prescribed time. Should thisnot be the case as may frequently happen with war ammunitionand ignitiontake place with a certain retardation, it is just possible-in the mostunfavorable case-that it may take place in the precise moment in which,as a result of the rebound of the rear breech part, the breech isunlocked. Destruction of the weapon and danger to the gunners life arethe unavoidable consequences.

The present invention relates to a fire arm with one-piece breech, whichfor this very reason eliminates the drawbacks connected with thetwo-piece breech, and besides constitutes an extraordinarysimplification as to design, as compared with existing one-piecebreaches.

The automatic fire arm with one-piece breech according to the presentinvention is provided with a pre-tensioned energy accumulator whichmoves the locking organ into locking position as soon as the breechreaches its end position.

In the fire arm according to the present invention the principlehitherto constantly observed, which involved making the breech lockingof automatic fire arms positive, and in addition also stood in the wayof adopting other methods than those mentioned, has been dropped. Aswill be shown further on, this opens up possibilities of evolvingdesigns which in respect of simplicity are far superior to existingdesigns, without, at the same time, neglecting in any way the safetydevices obviously required in arms manufacture.

In the weapon according to the present invention, as shown in a firstconstructional example, the tensioning of the energy accumulator issuitably eifected by the organ provided for locking the breech. Theenergy accumulator itself can suitably be designed as a spring of suchdimensions as will enable it to take up the major part of the forwardtravel energy of the breech block, so that the breech block shall strikethe cartridge chamber with a lessened shock only.

The dreaded consequences of rebound alluded to above are thus reliablyeliminated, whilst securing on the other hand the advantage that in themoment in which the breech block enters the locking position, thereversal movement of the locking organ is also reliably brought about.In the first constructional example the locking organ is shaped as around lock gliding with its milled ends in a groove of the breech casingand, in the front breech position, rotating so as to catch, through itsmilled ends, in a hole of the breech casing. The round lock is suitablyprovided with a lever contacting with a body gliding in the cradleagainst the action of a spring, thus tensioning the spring until, in theextreme front breech position, this spring, by discharging theaccumulated energy, moves the lock into locking position.

The striker is also suitably controlled by the round lock itself, insuch a manner that the striker may only be released after the lockingposition has been reached.

According to a further constructionalexample a toggle (knee lever) couldbe used,' contacting with a fixed stop of the breech casing and thuslocking the breech block, the toggle being controlled in a mannersimilar to the round lock.

It may also be advisable to have the energy accumulator, i. e. thespring actuating the looking organ in the end position of the breechblock, controlled by the barrel recoil-by way of example-instead of bythe forward travel of the breech block. For this purpose, a lockingorgan to be released through the forward travel of the breech block maybe provided.

The accompanying drawings show in Fig. 1-13 several constructionalexamples of realisation of the present invention. In such drawings:

Fig. 1 is a section through a fire arm schematically represented.

Fig. 2 a view of the locking organ in perspective,

Figs. 37 the various positions of the locking organ,

Fig. 8 a section through the striker control mechanism in the openposition of the locking organ.

Fig. 9 a section through the striker control mechanism in the lockedposition of the locking organ,

Fig. 10 a section through a constructional example in which the springtensioning is brought about by the barrel recoil,

Fig. 11 a section through a fire arm in which a toggle (knee lever) isused as locking organ,

Figs. 12-13 two different positions of the knee lever.

The fire arm consists in known manner of a breech casing in which thebarrel 2 is inserted by means of a bayonet joint. The breech casingslides on the cradle 3, against the spring 4. The breech block 5 slidingin the breech casing stands under the action of the recuperating spring6. In the cradle is a body 1 which can move forward and backward on thecradle against the spring 8. The locking organ 9 designed as a roundlock has two milled ends I!) by means of which the locking organ slidesin slots ending in a hole l2. The round lock 9 is fitted with a lever |3at the end of which there is a roller M. In the course of the forwardtravel of the breech block, as shown in Fig. 3, the roller l4 firststrikes the body During the further forward travel of the breech blockthe spring 8 is tensioned, so that the body 1 takes up the positionshown in Fig. 4. As soon as the milled ends I!) of the round lock reacha position in front of the hole l2, coinciding with the breech blockfront position, the energy accumulated in the spring 8 forces back thebody and the lever l3 as well, thus moving the milled ends I intolocking position, as shown in Fig. 5.

Upon release of the shot the barrel travels rearward together with thebreech casing, and the lever l3, i. e. its roller I4, comes into contactwith the rear edge of a corresponding recess of the body i. On thebreech casing and barrel moving further back, the lock is caused torotate out of the locked position, as shown in Fig. 6, and to occupy theposition shown in Fig. 7, in which the breech block is able to travelrearwardly against the action of the recuperating spring, under theaction of the remaining gases.

The special design of the locking organ and its control mechanism ensurean extremely simple and reliable striker control. As shown in Figs. 8and 9, the round lock 9 is provided with two milled recesses l and I6through which the striker is controlled. The striker itself is seated ina hole l8 and stands under the action of a spring l9. As shown in Fig.8, the striker possesses two turned grooves 20 and 2|; the body 22catches through a nose 23 into the groove 20, whilst a nose 24 of thebody 22 catches into the lit recess l6 of the round lock. The body 22 isslidingly seated in the breech block and stands under the action of aspring 25. The edge of the recess l5 of the round lock catches into thegroove 2|. The above description and figures clearly show that as longas the round lock 9 occupies the unlocked position, the striker cannotbe released since it is held by the edge of the recess l5. In addition,it is locked by the body 22, the nose 23 of which catches into thegroove 20. If now the round lock 9 is rotated into its locked position,

the edge of the recess l5 first liberates the striker.

The striker, however, is still unable to travel forward, since it isstill secured by the nose 23. Not before the lock 9 nearly reaches itsfinal locked position will the edge of the recess |6 strike the nose 24,thus forcing downward the body 22 and withdrawing the nose 23 out of thegroove 20. The striker is now free and, under the action of the springI9, is hurled against the detonator. As soon as the lock is rotated backfrom the locked position into the unlocked position the edge of therecess l5 again catches into the groove 2|, moving the striker back intothe position shown in Fig. 8, at the same time tensioning the spring H].

In the further constructional example of a fire arm according to thepresent invention-as shown in Fig. l0-a body sliding in the cradle isagain provided, standing under the action of the spring 8. The spring 8,however, does not contact with a part rigidly connected with the cradle,but, on the contrary, with a part rigidly connected with the barrel. Thebreech casing carries a locking lever 21 swinging round a bolt 26, whichlever, through a nose 28, catches into a corresponding recess 29 of thebody The locking lever 21 stands under the action of a spring 30 whichhas the tendency to keep it within the recess 29 of the body 1. A cam 3|of the locking lever 2'! lies in the path of a stop 32 of the breechblock 5. The tensioning of the spring 8 is here brought about, not bythe forward travel of the breech block, but by the barrel recoil; thelocking lever 27 catches into the recess 29 of the body 1, keeping thespring 8 tensioned, so that the body I, together with the barrel and thebreech casing, again travels forward.

When the breech block reaches its front end position, it hits throughits stop 32 the cam 3| of the lever 21, thus causing the latter torotate, and consequently to release the body 7. Under the action of thespring 8 the round lock 9 is thus rotated and the breech block islocked.

Figs. 11 and 12 show a constructional example in which, in place of theround lock, a toggle (knee lever) 33 is provided. The knee lever 33,swivellingly seated in the breech block, catches through its end 34behind a face 35 of the breech casing, thus locking the breech block.

As shown in Figs. 12 and 13, the control mechanism is similar to theconstructional example according to Figs. 1-7.

I claim:

1. Automatic fire arm comprising a barrel, a breech casing, a one-piecebreech block slidable in the casing, a locking member associated withthe breech block, and a pre-tensioned energy accumulator operative tomove the looking member into locking position as the breech blockreaches its forward end position, said locking member including arounded portion and being provided with milled ends, the breech casinghaving slots within which said milled ends slide and ending in acircular bore within which said rounded por- 5 tion can rotate when themilled ends clear the slots.

2. Automatic fire arm comprising a cradle, a barrel slidable relativethereto, a breech casing, a one-piece breech block slidable in thecasing, a locking member associated with the breech block, apre-tensioned energy accumulator operative to move the locking memberinto locking position as the breech block reaches its forward endposition, the energy accumulator comprising a spring arranged to beacted upon by a part of the barrel to be tensioned by the barrel recoil,and a locking device acting to hold the spring in tensioned conditionand arranged in the forward path of the breech block to be released bythe breech block as it reaches its extreme forward position.

3. Automatic firearm comprising a barrel, a breech casing, a one-piecebreech block slidably mounted in the casing, a locking member mounted onthe breech block and held in nonlocking position during the forwardmovement of the breech block, said casing being provided with a cutoutfor the locking member so positioned as to enable said member to bemoved into locking position relative to the breech block 'as the blockreaches its forward end position,

and an energy accumulator acted upon by the breech block to store energyduring the forward travel of the block, said energy accumulator actingon the locking member to move the same into position against the breechcasing as soon as such member is free to move relative to the breechblock.

HANNS LIPPERT.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

